Disinfectant



Reissued Apr. 30, 1946 DISINFECTANT Wendell n. Tisdale, Wilmington, DeL,and Ira Williams, Berger, Ten, assignors to E.

Pont de Nemours 8.: Company, Wilmington, Del., a corporation of DelawareNo Drawing. Original No. 1,972,961, dated September 11, 1934, Serial No.540,202, May 28, 1931. Application for reissue August 20, 1945,

Serial No. 611,684

13 Claims.

This invention relates to disinfectants, and more particularly tomethods and means of controlling and preventing growth of fungi andmicrobes.

The use of sulfur, sulfides, lime sulfur, and various mixturescontaining free or sulfide sulfur, phenol compounds, and mercurycompounds has been suggested for disinfecting and fungieidai purposes.Various sulfur containing organic substances, thioureas, and certainxanthates have also been described for this purpose, but for one reasonor another have not been wholly satisfactory. Certain of these compoundsalso have the disadvantage of being toxic to human beings coming incontact with them.

An object of our invention is a disinfecting material that is not onlyuseful as a general disinfectant but is particularly useful as afungicide and as a microbicide. A further object of our invention is amaterial for this purpose that is non-toxic. Another object of ourinvention is to provide a means for preventing the attack of wood,cotton, leather, fruit, plants and other organic material by fungus andsimilar growth. A still further object of our invention is to provide ameans to arrest the attack of these organic materials by fungi, bacteriaand the like. Other objects will be apparent as the specificationproceeds.

These objects are accomplished by the following invention whichcomprises treating the plants or other organic material with aderivative oi a dithiocarbamic acid in such manner that thedithiocarbamic acid derivative comes in contact with the parts to beprotected or the fungi to be destroyed. We preferably apply thesederivatives in the form of a solution, emulsion, or powder.

The materials which we employ in our method of protecting against orkilling fungi are solid or liquid derivatives of dithiocarbamic acid,which contain the unaltered arrangement of nitrogen, carbon and two'sulfur atoms.

Dithiocarbamic acids are those products resulting from the interactionof carbon disulfide with the more basic amines, which contain at leastone hydrogen attached to the nitrogen.

Among the amines which are satisfactory for this purpose are thosealiphatic primary and secondary amines, which contain as substituentssuch groups as methyl, ethyl, ethanol, propyl, isopropyl, butyl,isobutyl, amyl, isoamyl, benzyl,

alLyl, crotyl, b-amino ethyl and cyclohexyl and cyclic amino compoundssuch as piperidine and methyl plperidine. Aromatic amines such as methylaniline, ethyl aniline, ethyl toluidine and propyl xylidine are alsosuitable.

One mole of an amine can be represented as combining with one mole ofcarbon disulflde to form the ditbiocarbamic acid in which formula X ishydrogen or an alkyl radical. Y may represent hydrogen, an alkyl or arylradical. The free acids as represented are somewhat unstable, and incarrying out the process of our invention we employ those derivatives inwhich the hydrogen is replaced and which may be represented by theformula In this formula Z may be a metal, or metallic in nature, or asalt forming element or radical such as ammonium, or a derivative suchas dior triphenyl guanidine, or alkyl or aryl radicals,

and we find that all compounds which contain this characteristic groupare of value for the control of fungi of various kinds. By the properchoice of the substituents X, Y and particularly of Z the physicalnature, solubility and other physical properties may be varied to bestsuit the sulfide and tetramethyl thiuram disulfide.

requirement. For example. ii X and Y are ethyl radicals and Z is theradical I l 1 where and Y are ethyl radicals, a liquid product isobtained from which emulsions may be prepared. 1! Z is sodium,potassium, calcium or a similar metal or a radical such as ammonium,methyl ammonium or dimethvl ammonium, water soluble products are formed.It Z is a metal such as zinc, mercury, copper or iron, solid materialsalmost completely insoluble in water will result.

Modifications of the variables also permit 01 combining toxic or othervaluable groupings with the group. For an example, a dlthiocarbamic acidmay be madeto combine with an alkaloid to produce the valuableproperties of each. The following examples are not to be construed aslimitations'oi, but serve to illustrate certain methods of carrying outour invention.

Example I One part of finely divided ferric dimethyl dithiocarbamate wasadded to 250 parts or sterile nutrient agar. Two tubes were inoculatedwith a pure culture of isperaillus niger. Two tubes were inoculated witha pure culture of Fomes annosus. In each case growth was inhibited.

Example II The process of Example I was repeated using cadmium methylethyl dithiocarbamate with substantially the same results.

Example III The process of Example I was repeated using the triphenylguanidine salt of dimethyl dithiocarbamic acid with substantially thesame results.

Example IV Th process oi Example I was repeated using tetramethylthiuram disulfide with substantially the same results.

Example V Freshly sawed pine was dipped in an emulsion of allyl-dimethyldithiocarbamate and a sodium salt. When stacked near similar untreatedmaterial the treated material remained bright, while the untreatedmaterial became badly stained by fungi.

' Example VI The process of Example V was repeated with a solutionsaturated with tetramethyl thiuram This solution prevented staining.

Example VII Cloth was impregnated with a warm 0.1 per 1 cent solution ortetramethyl thiuram sulfide and stored under warm damp conditions. Thetreated sample remained in good condition, while an untreated sample wasafiected with mold.

Example VIII 0.1 cc. of a culture of Staphylococcus aurens in broth wasadded to 5 cc. of a 0.2 per cent solution of sodium dimethyldithiocarbamate. Alter fliteen minutes, neutral broth was inoculatedwith one drop or this mixture. No growth resulted when the culture wasincubated at 87 C. for 48 hours. I

Example I)! Wallboard made i'rom pine wood was impregnated with aboiling 0.2 per cent solution 0! tetra.- methyl thiuram sulfide. Thesetest pieces were then placed in test tubes containing growing culturesof Fame: annom. After three week at 25 0. untreated samples showedconsiderable shrinkage and signs of decay, while thetreated sample hadlost no weight and showed no signs 0! decay.

Example x Example XI The conditions of Example X were repeated using 0.1per cent solution of sodium dimethyl dithiocarbamate. No germinationresulted.

Example XII Smut infested barley was treated as in Example X with a 0.1per cent solution or allyl-dimethyl dithiocarbamate and 0.25 per cent ofdibutyl ammonium oleate. No germination oi spores resulted.

Example XIII The process oi Example XII was repeated using 0.1 per centethyl-dimethyl dithiocarbamate. Only a trace of spore germinationresulted.

Example XIV The process 01' Example XII was repeated using 0.1 per centtetra-ethyl-thiuram-monosulfide. Approximately 50 per. cent of thespores were killed. Example XV The process oi Example XII was repeatedusing 0.1 per cent sodium butyl dithiocarbamate. Approximately 70 percent of the spores were killed.

The foregoing examples will serve to illustrate certain methods andmeans of carrying out our invention, but various modifications andequivalents will .be apparent therefrom. For example, calcium,magnesium, or similar metals may be used to replace the sodium orpotassium when a less alkaline solution is desired, or heavy hydrocarbonradicals may be substituted for X, Y or Z to promote oil solubility.

The methods of applying the material may be varied to include dusting ortumbling with powders, spraying with solutions. emulsions orsuspensions, or soaking in solvents containing the active ingredient orthe material may be applied directly as a paint or paste, or in acoating. We have also found that in some cases it is desirable to use awetting-agent such, for example, as Penetrol. In place of Penetrol,other wetting agents may be used, such, for example, a the alkylatednaphthalene sulionic acids known in the trade as v diseases caused bybacteria, fungi, insects, mites.- etc., can be prepared. The stablenature of certain of these preparations may in many instances make themof value for internal use. Other obvious applications are thedisinfection of instruments, laboratories, dairy equipment, etc.

A further advantage of this invention resides in the high activity ofthese derivatives, which at the same time are non-toxic and free fromirritating effects on the operator, or anyone coming in contact with thematerials. For these reasons, these compounds are particularly valuableas general disinfectants and are very effective for the treatment oflumber or similar forms of wood for the prevention of the growth oforganisms that,

cause decay in wood, such, for example, as Coniphora cerebella, Fomesannosus, and of those organisms that cause so-called "blu rot, "bluestain." or sap stain" of lumber, such as Ceratostomella group or theGraphium group.

While certain illustrative embodiments of our invention have been givenin the foregoing, it is to be understood that other embodiments will beapparent therefrom and may be practiced within the scope of ourinvention, and that we do not intend to be limited except as indicatedin the following patent claims.

We claim:

1. In a method of disinfecting for the control of bacteria, microbes,and fimgi, the step comprising contacting the organism with adisinfectant comprising a derivative of dithiocarbamic acid whichcontains the group 2. In a method of disinfecting for the control ofbacteria. microbes, and fungi, the step comprising contacting theorganism with a disinfectant comprising the reaction product of carbundisulflde and an amino compound, said product being represented by theformula 1: gar-(5+2 in which x is hydrogen or an alkyl radical, Y ishydrogen. an alkyl, or an aryl radical, and Z is metallic in nature, asalt forming element, an

ammonium radical, or an alkyl or aryl radical, or a group represented bythe formula where n may be any number from 1 to 3, or any other radicalwhich when the compound is sub-.

of bacteria, microbes, and fungi, the step comprising contacting theorganism with a disinfectant comprising sodium di-substituteddithiocarbamate.

8. In a method of disinfecting for the control of bacteria, microbes,and fungi, the step com-- prising contacting the organism with-adisinfectant comprising sodium dimethyl dithiocarbamate.

9. A disinfectant useful as a bacterlcide, microbicide. and fungicide,the disinfectant being a powder, an emulsion, or a suspension,comprisinga derivative of dithiocarbamic acid which containsthegroup 10.A disinfectant, useful as a bactericide, mi-

crobicide,'and fungicide, comprising a derivative of dithiocarbamic acidwhich contains the group and a wetting agent.

11. A disinfectant, useful as a bactericide, mi-

crobicide. and fungicide, comprising the reaction product of carbondisulilde and an amino compound, said product being represented by theformula V Km.-. a

inwhichxishydrogen oranalkylradicaLYis hydrogen, an alkyl, or an arylradical, and Z is metallic in nature, a salt forming element, an

- ammonium radical, or an alkyl or aryl radical, or

a group represented by the formula where'n may be any number from 1 to3, or any other radical which when the compound is sub- ,iected tohydrolysis in aqueous sodium hydroxide will result in the formation ofthe sodium salt of dithiocarbamic acid, and a wetting agent.

12. The disinfectant of claim 11 in which Z is a metal taken from agroup consisting of zinc, e y. copp r. and iron.

13. A disinfectant, useful as a bactericide, microbicide, and fungicide,comprising a tetra-substituted thiuram monosuiiide and it getting agent.

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